Abstract Rationale Particulate matter (PM) exposure and metabolic syndrome(MetSyn) are linked to cardiorespiratory disease, although mechanisms remain indeterminate. We previously showed a murine model of World Trade Center-PM exposure lead to cardiorespiratory and vascular changes, and now further demonstrate the inflammatory and oxidative stress changes after addition of high fat diet as a model of MetSyn. Methods Female C57Bl/6J mice were fed high-fat diet (HFD, ResearchDiets D12492) or normal-diet (ND) for 12 weeks, followed by single oropharyngeal aspiration of 100ug WTC-PM53 or PBS. After 24 hours, plasma and BAL were collected and analyzed for 69 cytokines/chemokines (68-plex Millipore Luminex100; HO-1 abcam ELISA). Ingenuity Pathway Analysis (IPA) was used to predict upstream regulators. Lung tissues were NP40-extracted and probed for HO-1 (abcam), RAGE (sc-365154), NFκB(p52) (sc-7386), and β-Actin (Sigma) by capillary-based western(12-230 KDa; ProteinSimple Wes). Results Heatmaps of 31 Plasma (Fig1A) and 40 BAL (Fig1B) analytes with significantly different elaboration between any two exposure groups were generated using semi-supervised clustering, missMDA imputation for 25% missing data, and identified four clusters of inflammatory patterns within each exposure. Plasma. Compared to ND-PBS, ND-PM showed increased expression in Cluster 3; HFD-PBS showed increased expression in all clusters, with decrease in Clusters 3-4 in HFD-PM. Eotaxin, IL-28B, IL-16, IP-10, KC, MIP-2, MCP-3, IL-20, sCD137, and MDC were significantly increased in HFD-PBS/ND-PBS, and attenuated with HFD-PM co-exposure. BAL. Cluster 4 increased in both PM exposures and Clusters 1-2-4 increased in HFD-PM. IFNβ, IL-1β, IL12(p70), IL-13, IL-17A, M-CSF, FLT3L, Exodus-2, Betacellulin, MCP-5, MIG, MDC, IL-6, IL-18, IP-10, VEGF-A and KC were significantly elevated in HFD-PM/ND-PBS. HFD-PM had synergistic elaboration of Exodus-2, Betacellulin, MCP-5, MDC, IL-6, IP-10, MIG, and VEGF-A. Western. HO-1 increased after PM exposure in ND and HFD, with co-exposure significantly higher than ND-PBS, Fig1C. RAGE and NFκB(p52) increased with HFD. Biomarker. IPA suggests significant inhibition of HO-1 and activation of RAGE in both HFD-PM/HFD-PBS and HFD-PM/ND-PBS BAL. NFκB2 had trends toward activation in the same groups. IPA also identified activation of NLRP3, IRF1, and STAT3 within the top canonical pathway, Pathogen-Induced Cytokine Storm Signaling Pathway, in HFD-PM/ND-PBS BAL. Fig 1D. Conclusion This murine model highlights HO-1, RAGE, and NFκB(p52) with key roles in inflammatory pathways after MetSyn and PM that could lead to cardiorespiratory dysfunction. The projected activation of upstream regulators NLRP3, IRF1, and STAT3 and the overlap with pathogen-induced cytokine storm is supported by the literature, and may be potential targets for future studies. This abstract is funded by: U01OH011855
Bernier et al. (Fri,) studied this question.